Studies were initially conducted to determine the action of
intravenous serotonin on perfused segments of human umbilical
cords in vitro. Intravenous serotonin, via bolus injection or
continuous infusion, was found to elevate venous perfusion pressure,
while intra-arterial serotonin failed to alter venous pressure.
Norepinephrine, administered to the venous perfusate, was...
Pineal hydroxyindole-0-methyltransferase (HIOMT) activity
was monitored over a 24 h period under three different photoperiods,
16L:8D, 8L: 16D, and 12 L:12D. It was observed that in all three
groups of fish HIOMT activity was high' during the dark portion of the
photoperiod in comparison to activity during the light portion....
Wheat is an important part of a healthy and balanced diet, requiring six servings per day to maintain a recommended 2000 Calorie intake (McRae, 2017). Because of this more land than almost any other kind of cereal is set aside for the purposes of growing wheat. To keep up with...
While it can be said that peer mentor-mentee relationships in college can lead to meaningful connections and interpersonal support, there is a lack of literature about how exactly mentor-relationship connections are made. This study examines the relationship building strategies that peer mentors used to connect with their mentees in the...
Significant use of cold in-place recycling (CIR) has occurred in
Oregon since 1984 as an alternative to other rehabilitation techniques
or to the reconstruction of distressed asphalt concrete (AC) pavements.
Due to the initial success of the projects cold recycled during 1984-85,
the Oregon Department of Transportation (ODOT) and Oregon...
A method has been developed for the continuous automated monitoring
of cardiac output in adult rainbow trout. Average cardiac output measured under
control conditions and varied environmental conditions of hypoxia and post-hypoxia
was significantly higher (P≤ 0.05) in male than female trout. The cardiac
output of trout in spawning condition...
There is evidence that recent ecological changes in lakes and their watersheds can be detected from analysis of lake sediments. This study was initiated to correlate
changes in some sediment characteristics of four Oregon lakes with past cultural developments of the lakes and their watersheds. The lakes chosen for this...
Global Positioning System (GPS) and Geographic Information System (GIS) technologies were employed to evaluate cattle occupancy of three landscape attributes on three different grazing allotments administered by the Wallowa Whitman National Forest in Northeast Oregon. Topographic characteristics of slope; 0-4%, 4-12%, 12-35% and >35% were evaluated as well as north...
Pineal acetylserotonin methyltransferase (ASMT) activities
in rainbow trout were reported on by Hafeez and Quay (1971). The validity of certain
assay parameters used by these researchers
were investigated. With the exception of incubation temperature,
all parameters studied proved to be quite valid. Temperature
studies indicated a low stability for trout...
The utero-ovarian vasculature of domestic animals has been a
popular research subject, especially concerning the roles of the uteroovarian
artery and vein in the unilateral luteolytic phenomenon
demonstrated in these animals. No reports in the literature, however,
have been found regarding the smooth muscle physiology of these vessels.
The present...
Productivity Interfirm Comparison (PIC) is a simple
method used to improve productivity at the firm level,
where a number of firms operate in the same product line so
that performance information on the firms can be compiled
and compared. This results in identifying potential areas
for improvement or exploitation. The...
Dietary protein intake has been observed to influence the induction
of cancer in animals exposed to carcinogens, presumably by affecting the
activities of enzyme systems which metabolize them. One such carcinogen
is aflatoxin B₁ (AFB₁) a mold metabolite and frequent contaminant of
foodstuffs. Variations in the levels of dietary proteins...
The emergence of high explosives on the battlefield can be defined both literally and figuratively as a seismic event in the landscape of modern warfare. High explosives first came into common use in war in 1914. By the end of World War I just four years later, more than 2.5...
Hereditary variation is a vital component in the development of new and improved cultivars of landscape plants. Sources of hereditary variation include naturally occurring variation, recombination due to controlled crosses, artificial mutagenesis, and genetic modification via biotechnology. Here I explore all methods with the exception of genetic modification via biotechnology....
Childhood cancers are rare diseases that affect 188 children in Texas for every million born. Leukemia is the most common childhood cancer and accounts for roughly one third of childhood cancer cases. However, it is estimated that only 10% of childhood cancer cases can be explained by known risk factors....
The validity of the widely used stochastic linearization
method for analysing the response of guyed towers to stochastic loads
is investigated. The governing equations of a guyed tower have two
main sources of nonlinearities, fluid-structure interaction and the
restoring force of the cables. In this study, two models are
considered....
Climate exerts considerable control on wildfire regimes, and climate and wildfire are both major drivers of forest growth and succession in interior Northwest forests. Estimating potential response of these landscapes to anticipated changes in climate helps researchers and land managers understand and mitigate impacts of climate change on important ecological...
Boreal and temperate biomes host nearly half of the earth’s forested ecosystems. The temperate rainforests of the Pacific coast of North America constitute nearly half of all temperate rainforests on earth. Along the northern extent of this region, the perhumid and sub-polar rainforests of southeast and southcentral Alaska are among...
The purpose of this paper is to compare the estimated production of the pendulum swing logging system to the production of a conventional balloon logging system. Cycle Time is established for the conventional system by time study techniques. A combination approach is used to model the pendulum system. A computer...
Response from nitrogen and chloride fertilization was measured
in field experiments on winter wheat (Triticum aestivum L. Em.
Thell. var. 'Stephens' and 'Yamhill') grown in western Oregon in an
environment with a range of susceptibility to take-all root rot
(Gaumannomyces graminis var. tritici Walker). Cropping sequences
and expected disease severity...
The utilization of ⁷⁷ [superscript m] Se, half life 17.5 s, and ⁷⁵ Se, half life 119.8 d, for quantification of trace amounts of Se in well water and biological materials by means of instrumental neutron activation analysis (INAA) is described. A Se detection limit of 0.03 ppm was achieved...
The public controversy over possible health hazards from radioactive fallout from atomic bomb testing began in 1954, shortly after a thermonuclear test by the United States spread fallout world wide. In the dissertation, I address two of the fundamental questions of the fallout controversy: Was there a threshold of radiation...
From a landscape ecology perspective, meadows are often seen as landscapes in
transition. Succession and change in meadows may be investigated by considering the
physical and anthropogenic factors that influence the landscape through time. What is
often unknown is how changes occur and how physical and anthropogenic factors
contribute to...
I studied developmental rates in a suite of temperate and tropical passerine bird species from the New World to test the hypothesis that tropical passerines exhibit slower patterns of growth and development than temperate birds. I also investigated how the expression of several developmental rates varied with life history traits...
The Klamath-Siskiyou Ecoregion of southwest Oregon and northern California is greatly departed from its historic, mixed-severity fire regime. This departure manifests in larger wildfires, greater proportions of high burn severity within wildfire perimeters, and decreased diversity of post-fire vegetation successional stages and trajectories across the landscape compared to historical norms....
The 180,000 km² of Arabian lava fields (“harrats” in Arabic) form one of the largest distributed basaltic provinces in the world. Approximately 50% of these are located in Saudi Arabia. The most recent eruption in 1256 AD, as well as seismicity and ground deformation associated with shallow dike emplacement in...
The spread of nonnative species across the globe has contributed to biodiversity loss and changes in ecosystem structure and function. Monitoring the introduction, naturalization, and spread of introduced species is critical in abating negative impacts wrought by species invasions. However, providing basic information concerning the presence or spread of many...
The salt marshes of the Salmon River Estuary, Oregon have been of interest for decades due to their disturbance and restoration history, as well as the presence of long-term vegetation transects that were established as early as the 1970s. Vegetation abundance data have been gathered in the four sites of...
Arctic-boreal regions are exhibiting the symptoms of profound ecological shifts as they experience pronounced warming. Wildlife in high-latitudes are one such harbinger of change, and their populations are undergoing range-shifts, declines, and extinctions in response to their rapidly altering habitats. As the circumpolar and boreal north is snow-covered for up...
In this thesis we study mathematical and computational models for phenomena of flow and transport in porous media in the presence of changing pore scale geometries. The differential equations for the flow and transport models at Darcy scale involve the coefficients of permeability, porosity, and tortuosity which depend on the...
Classic biological control can be a powerful option for those tasked with managing biological invasions; however, some biocontrol releases lead to non-target attack – feeding, damage or development on species other than the target species. The cinnabar moth, Tyria jacobaeae L. (Lepidoptera: Erebidae) was introduced to Western Oregon as a...
Several solar energy models exist, but all models must balance: computational runtime, light complexity, and model output volume. These models span the spectrum of simplistic global solar energy equation sets to complex light ray-tracing models. Spatiotemporally inaccurate representations of solar energy may cause compounding simulation effects and introduce unknown modeling...
The human health effects of exposure to numerous single environmental contaminants have been well characterized. Yet, biomonitoring studies have detected multiple environmental chemicals in humans, highlighting the need to investigate the health effects of exposure to multiple environmental chemicals. Environmental data is highly complex, therefore current methods of defining environmental...
Visualizing large movement datasets with flow maps is difficult because overlapping flows create significant graphical conflicts that make accurate interpretation difficult or impossible. Interactive flow mapping applications allow users to explore large movement datasets by automatically generating flow maps from subsets of the data in response to queries by the...
Efficient foraging strategies result in a predator spatially overlapping with its prey, foraging in the most profitable patches, and minimizing the time transiting between patches. Previous studies investigating baleen whale foraging strategies have generally focused on investigating spatial overlap with prey patches, patch profitability or movement within feeding grounds. The...
In this thesis we study a numerical analysis problem motivated by the need to simulate an event such as an oil spill in a deep water environment. Numerical simulation can help to mitigate the disastrous effects of such events by aiding the management of risk assessment and recovery efforts.
However,...
As a young adult, I have been able to witness first hand just how drastically social media is changing our culture and the way that we look at things. As social media continues to become more vastly used by its members who are in many different phases of life and...
The major purpose of this study was to determine if
there were significant differences in the self-concepts of
vocational education teacher-trainees, non-vocational education
teacher trainees and non-education students at
Montana State University.
Two hundred students were surveyed to determine if
there were any differences in self-concepts based on
either major...
Purpose of the Study
The study was an examination of the effect of utilizing the
DECA Merit Awards Program (MAP) materials on high school
distributive education student interest levels toward careers in
marketing. It compared three groups of high school distributive
education students who used MAP with three groups who...
Five simulated precipitation patterns characteristic of the Columbia
Basin and Plateau region and six fertilization rates were evaluated
for their effect on percent crude protein, percent in vitro dry matter
digestibility, fiber content, and yield of wheat aftermath on a commercial
farm in north central Oregon.
The higher moisture regimes...
Directional wave spectra have been estimated in this study based
upon simultaneous subsurface measurements of current and pressure.
Two previously developed methods, the stochastic and deterministic
approaches, have been reviewed and restudied. It is demonstrated by
means of the Correlation Theorem that the stochastic and deterministic
approaches are, under certain...
Purpose: The general problem was to determine the relationship between biorhythms and injuries to college football participants representing Oregon State University. Procedures: The population consisted of one hundred and ninty two football players representing Oregon State University who participated in the intercollegiate football seasons of 1981 and 1982. Injury data...